1. Field of the Invention
The present invention relates to a winding process for an elastomeric fiber package and, more particularly, to a process for winding a package utilizing a contact roll exerting variable pressure during the winding.
2. Description of Background Art
Products based on elastomeric fibers have been used in many areas such as industrial materials, clothing, and disposable personal care products (for example diapers). The elastomeric fibers have been woven and knit into fabrics, stitch-bonded into nonwovens, and directly adhered onto sheet materials such as nonwovens and films. The elastomeric fiber is ordinarily provided wound onto tubecores. The woundfiber and associated tubecore are referred to as a xe2x80x9cpackagexe2x80x9d. In use, the elastomeric fiber is unwound from the package sequentially or in parallel, either passively (for example, by xe2x80x9cover-end take-offxe2x80x9d) or actively (for example by xe2x80x9crolling take-offxe2x80x9d), and fed to a downstream process.
However, there have been problems in that elastomeric fiber packages have heretofore sometimes had poor package shape. Such packages have been wound with rising force of the contact roll on the tubecore and package. This poor package shape can cause the elastomeric fiber to slough off the package readily (for example as a result of rubbing against shipping materials or other elastomeric fiber packages) so that the unwinding elastomeric fiber becomes entangled with the sloughed-off elastomeric fiber, leading to breaks in the fiber. Such breaks also occur as a direct result of the rubbing. As a result, the economics of unwinding fibers from such packages were poor, and an improved process for winding elastomeric fiber packages is needed.
The process for winding an elastomeric fiber producing an inflected force profile, comprises the steps of:
(A) rotating a tubecore in contact with a contact roll;
(B) winding the fiber onto the tubecore so that the contact roll exerts an initial force against the fiber on the tubecore and a package begins to be formed;
(C) gradually reducing the force a first time during the first 30% of winding time to approximately 25-60% of the initial force;
(D) holding the force substantially constant until the final 30% of winding time; and
(E) reducing the force a second time to no less than approximately 10% of the initial force.